Search results for "ISMU"
showing 10 items of 685 documents
Effect of xanthine oxidase-generated extracellular superoxide on skeletal muscle force generation
2009
Skeletal muscle contractions increase superoxide anion in skeletal muscle extracellular space. We tested the hypotheses that 1) after an isometric contraction protocol, xanthine oxidase (XO) activity is a source of superoxide anion in the extracellular space of skeletal muscle and 2) the increase in XO-derived extracellular superoxide anion during contractions affects skeletal muscle contractile function. Superoxide anion was monitored in the extracellular space of mouse gastrocnemius muscles by following the reduction of cytochrome c in muscle microdialysates. A 15-min protocol of nondamaging isometric contractions increased the reduction of cytochrome c in microdialysates, indicating an …
TORC1 Inhibition by Rapamycin Promotes Antioxidant Defences in a Drosophila Model of Friedreich’s Ataxia
2015
Friedreich's ataxia (FRDA), the most common inherited ataxia in the Caucasian population, is a multisystemic disease caused by a significant decrease in the frataxin level. To identify genes capable of modifying the severity of the symptoms of frataxin depletion, we performed a candidate genetic screen in a Drosophila RNAi-based model of FRDA. We found that genetic reduction in TOR Complex 1 (TORC1) signalling improves the impaired motor performance phenotype of FRDA model flies. Pharmacologic inhibition of TORC1 signalling by rapamycin also restored this phenotype and increased the lifespan and ATP levels. Furthermore, rapamycin reduced the altered levels of malondialdehyde + 4-hydroxyalke…
Mandibular osteoma as a cause of ankylosis and progressive trismus.
2021
Osteomas are benign tumours of bone tissue restricted to the craniofacial skeleton. The aim of this article is to present and discuss the demographic and clinical aspects and the management of craniomaxillofacial osteomas. When the patient was submitted from primary care to our hospital, he was 68 years old, and he had ankylosis of the temporomandibular joint for the previos 4 years. A CT scan was performed, finding a giant mandibular osteoma. Conservative treatment and radiological follow-up were carried out with clinical stability. Osteomas more often are seen in the paranasal sinuses and in young adults, with no differences in gender. Most are asymptomatic, but they can cause local probl…
Iridoid extracts from Ajuga iva increase the antioxidant enzyme activities in red blood cells of rats fed a cholesterol-rich diet.
2010
The lyophilized aqueous extract of Ajuga iva (Ai) is able to reduce oxidative stress, which may prevent lipid peroxidation in hypercholesterolemic rats. Iridoids (I) were isolated from Ai. We hypothesized that the antioxidant defense status in red blood cells (RBC) and tissues in rats fed a cholesterol-rich diet and treated with Ai may be correlated to these compounds. Male Wistar rats (n = 32) weighing 120 +/- 5 g were fed a diet containing 1% cholesterol for 15 days. After this phase, hypercholesterolemic (HC) rats were divided into groups, fed the same diet, and received either the same or different doses (5, 10, or 15 mg/kg body weight by intraperitoneal injection) of I for 15 days. Com…
Mitochondria from females exhibit higher antioxidant gene expression and lower oxidative damage than males
2003
We have investigated the differential mitochondrial oxidative stress between males and females to understand the molecular mechanisms enabling females to live longer than males. Mitochondria are a major source of free radicals in cells. Those from female rats generate half the amount of peroxides than those of males. This does not occur in ovariectomized animals. Estrogen replacement therapy prevents the effect of ovariectomy. Mitochondria from females have higher levels of reduced glutathione than those from males. Those from ovariectomized rats have similar levels to males, and estrogen therapy prevents the fall in glutathione levels that occurs in ovariectomized animals. Oxidative damage…
Antioxidant enzyme activities and the production of MDA and 8-oxo-dG in chronic lymphocytic leukemia.
2001
Abstract Chronic lymphocytic leukemia (CLL) is a neoplastic disease susceptible to antioxidant enzyme alterations and oxidative stress. We have examined the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), and the oxidized/reduced glutathione (GSSG/GSH) ratio together with the levels of malondialdehyde (MDA) and 8-oxo-2′-deoxyguanosine (8-oxo-dG) in lymphocytes of CLL patients and compared them with those of normal subjects of the same age. SOD and CAT activity decreased in CLL lymphocytes while GPx activity increased. GSH content of CLL lymphocytes also increased, and GSSG concentration remained constant. Thus, a reduced GSSG/GSH ratio was obtaine…
Impact of cardiovascular risk factors on oxidative stress and DNA damage in a high risk Mediterranean population
2009
The impact of classic cardiovascular risk factors on oxidative stress status in a high-risk cardiovascular Mediterranean population of 527 subjects was estimated. Oxidative stress markers (malondialdehyde, 8-oxo-7′8′-dihydro-2′-deoxyguanosine, oxidized/reduced glutathione ratio) together with the activity of antioxidant enzyme triad (superoxide dismutase, catalase, glutathione peroxidase) were analysed in circulating mononuclear blood cells. Malondialdehyde, oxidized glutathione and the ratio of oxidized to reduced glutathione were signifi cantly higher while catalase and glutathione peroxidase activities were signifi cantly lower in high cardiovascular risk participants than in controls. S…
Decreased cell proliferation and higher oxidative stress in fibroblasts from Down Syndrome fetuses. Preliminary study
2013
Abstract Down Syndrome is the most common chromosomal disease and is also known for its decreased incidence of solid tumors and its progeroid phenotype. Cellular and systemic oxidative stress has been considered as one of the Down Syndrome phenotype causes. We correlated, in a preliminary study, the fibroblast proliferation rate and different cell proliferation key regulators, like Rcan1 and the telomere length from Down Syndrome fetuses, with their oxidative stress profile and the Ribonucleic acid and protein expression of the main antioxidant enzymes together with their activity. Increased oxidized glutathione/glutathione ratio and high peroxide production were found in our cell model. Th…
Activity of superoxide dismutase copper/zinc type and prognosis in a cohort of patients with coronary artery disease.
2015
Aim: Superoxide dismutase (SOD) is important to control reactive oxygen species, but the relevance to human disease like coronary artery disease (CAD) and underlying ischemia/reperfusion injury is not clarified. Methods: For this study, 2239 patients with known CAD were prospectively followed with a median follow-up time period of 3.6 years and a maximum of 6.9 years. During follow-up cardiovascular death was reported in 103 cases. Results: SOD activity (log-transformed) was investigated as continuous and categorical variable, showing a significant influence on outcome in the fully adjusted model (p = 0.045). Conclusion: Increased SOD activity beyond the normal range in the human physiolog…
REDUCED OXIDATIVE STRESS DURING ACELLULAR REPERFUSION OF THE RAT LIVER AFTER HYPOTHERMIC OSCILLATING PERFUSION
1999
Background ATP resynthesis during reperfusion after liver preservation has been shown to be well correlated with the function of transplanted grafts. Nevertheless, the advantages of a cellular energy charge loading during the preservation period are yet not fully understood. This study evaluates the effects of different nucleotide levels at the end of preservation on metabolic changes and oxidative stress during reperfusion. Methods Two experimental groups were chosen reflecting different energy charge states after preservation: static cold storage for 10 hr and hypothermic oxygenated oscillating perfusion for 10 hr. In both experimental groups, normothermic ex vivo acellular reperfusion ov…